/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.expression.spel.ast;

import org.springframework.asm.MethodVisitor;
import org.springframework.expression.spel.CodeFlow;
import org.springframework.expression.spel.support.BooleanTypedValue;

/**
 * Represents the literal values {@code TRUE} and {@code FALSE}.
 *
 * @author Andy Clement
 * @since 3.0
 */
public class BooleanLiteral extends Literal {

    private final BooleanTypedValue value;


    public BooleanLiteral(String payload, int pos, boolean value) {
        super(payload, pos);
        this.value = BooleanTypedValue.forValue(value);
        this.exitTypeDescriptor = "Z";
    }


    @Override
    public BooleanTypedValue getLiteralValue() {
        return this.value;
    }

    @Override
    public boolean isCompilable() {
        return true;
    }

    @Override
    public void generateCode(MethodVisitor mv, CodeFlow cf) {
        if (this.value == BooleanTypedValue.TRUE) {
            mv.visitLdcInsn(1);
        }
        else {
            mv.visitLdcInsn(0);
        }
        cf.pushDescriptor(this.exitTypeDescriptor);
    }

}
